Network diagrams are schematic displays of project schedule activities and the interdependencies between these activities. When developed properly, this graphical view of a project’s activities conveys critical schedule characteristics required to effectively analyze and adjust schedules – thus resulting in accurate and feasible schedules. This document addresses what should be considered in the development of a network diagram, how network diagrams are created, and how they may be analyzed to identify necessary corrective actions and ensure optimal schedule definition. Development stage – initial development
Function of routers
The routers in the network provide a gateway between the networks. Router 1 will provide a gateway to the Internet, Router 2 will provide a gateway between the workgroup networks; file server web server and the Isolation LAN, which will connect the administration network and the isolation LAN. The routers will select the best path using a metric which can be calculated on Hop count, bandwidth, delay, reliability and Load.
The metric hop count is used by OSPF (Open Shortest Path First) and RIP (Router Information Protocol), hop count is the number of routers the packet has to cross between source and destination. EIGRP (Enhanced Interior Gateway Routing Protocol) uses bandwidth and delay as default metrics but can also be configure to include bandwidth and reliability in this calculation which is a much more precise metric than Hop count. The routers are located in the core layer of the network and provide a gateway to the WAN. Application of routing protocols
Function of routing protocols
The routing protocol main functions are:
•Discovers directly connected neighbors
•Propagates routing information/ advertising known routes
•Update routing table
•Prevention of routing loops
The router establishes a connection between neighboring routers and then begins exchanging routing updates about each routers directly connected networks. The router updates all new information into its own routing table. Some protocols send routing updates when a specific timer elapses, or when a topology change occurs. Topology changes include:
•Failure of a link
•Introduction of a new link
•Router malfunction or failing
•Link configuration change
The updates that are sent can include the complete routing tables. EIGRP sends bounded updates which are non-periodic and are only sent to router that require that information which will have less impact on the performance of the network.
Top of Form
Developing security strategies that can protect all parts of a complicated network while having a limited effect on ease of use and performance is one of the most important and difficult tasks related to network design. Security design is challenged by the complexity and porous nature of modern networks that include public servers for electronic commerce, extranet connections for business partners, and remote-access services for users reaching the network from any ware, customer sites, hotel rooms, Internet cafes, and so on. To help you handle the difficulties inherent in designing network security for complex networks, this will help teaches a systematic, top-down approach that focuses on planning and policy development before the selection of security products (Dean, 2010).
The goal is to help you work with your network design customers in the development of effective security strategies, and to help you select the right techniques to implement the strategies. The describes steps for developing a security strategy and covers some basic security principles. The presents a modular approaches to security design that will let you apply layered solutions that protect a network in many ways. The final sections methods for securing the components of a typical home network that are most at risk, including Internet connections, remote-access networks, network and user services, and wireless networks.
Network design should be a complete process that matches the customers’ needs to available technology to deliver a system that will maximize an organization’s success. •In the LAN area it is more than just buying a few devices. •In the WAN area it is more than just calling the phone company. •A focus is placed on understanding data flow, data types, and processes that access or change the data. However a focus is placed on understanding the location and needs of user communities that access or change data and processes.
Therefore, several techniques and models can be used to characterize the system, new user requirements, and a structure for the future system. Moreover, a logical model is developed before the physical model. •The logical model represents the basic building blocks, divided by function, and the structure of the system. •The physical model represents devices and specific technologies and implementations. Below will show a top down design steps, then following that you will see the layout of design. This will show how the physical layout will be placed after the completion.
Workgroup switch Switch Wireless router
PC1 PC2 Printer File server Web server Laptop 1 Laptop 2
The cost for materials and instillations are as follow: Please note owner will provide 2 PC’s, 2 Laptops and a printer.
DSL router $286.03
Wireless router $90.00
(2) Switches $235.98
File server $887.99
Web server $779.99
Basic network architectures have also changed very little in Ethernet LAN design. I will provide four main choices: point-to-point (P2P), hub (or star), ring and mesh. The point-to-point and the more traditional hub network architectures remain the simplest to set up and manage, but both present single points of failure that must be factored into network resiliency and redundancy considerations. The ring architecture is slightly older and the wiring can be cumbersome to set up, but ring characteristics offer redundancy that is desirable for many organizations. With the client approval I may consider the mesh architecture for larger clients with the most stringent redundancy requirements and self-healing capabilities, but mesh is also the most complex to set up and manage.
The preferred approach is to provision separate VLAN segments on the existing branch switch platform for energy management. A single branch router can provide both the WAN access to the branch from the enterprise campus network, as well as the VPN access from the MSP network (with appropriate software image and licensing). In cases where an IPSec VPN provides the enterprise WAN connectivity, an additional VPN tunnel can be provisioned to the MSP network (Network Design Considerations for Cisco Mediator Deployments, 2012). In the case where private enterprise WAN connectivity is provisioned, a separate Internet connection could be provisioned on the branch router.
The Firewall feature set would be used to provide access control between the energy management systems VLANs and the rest of the network, including the MSP network. If a higher level of isolation is desired, IPSec VPN tunnels can be provisioned internally within the enterprise network (for example, between the Network Operations Center (NOC) and the branch router). Comparatively, this design option results in lower hardware and ongoing maintenance costs, but the management and reoccurring costs of an additional VPN connection for each branch location may prohibit the scaling of this implementation (Network Design Considerations for Cisco Mediator Deployments, 2012).
The goal of quality of service (QoS) is to provide more efficient and predictable network service by providing dedicated bandwidth, controlled jitter and latency, and improved loss characteristics. QoS achieves these goals by providing tools for managing network congestion, shaping network traffic, using expensive wide-area links more efficiently, and setting traffic policies across the network. QoS prioritizes voice, data, and web traffic to ensure that mission-critical applications get the service they require.
In terms of overall operational management of the network service, it is noted that the quality of the service is related to both the capability to carry the end user traffic without significant degradation of end to end performance and without high variability in end to end performance, and the financial capability of the network service provider to fund the acquisition of transmission and switching infrastructure to match the demand levels (Huson, 1994). However, It is noted that such considerations impact directly on network funding models, where there is a requirement to ensure that additional demand levels is accompanied by additional financial capability to delay resources to match the demand level.
Moreover, It is not proposed to describe various financial structures for network services within the scope of this document, other than to note that the financial structure must match both the requirements of the service itself to scale the resource investment to match demand levels, and match, to some extent, the expectations of the client base.
It must be noted that this is an area where there is considerable diversity in the current Internet environment, and there is no commonly agreed business model at this stage. The basic pricing mechanism is that pricing should reflect the requirement of the service provider to meet the costs associated with the service. The precise nature of these costs and how they are derived from the underlying resource costs area areas yet to be well understood across the Internet community.
Dean, T. (2010). CIS175: Network+ guide to networks: 2009 custom edition (5th ed.). Boston: Course Technology, Cengage Learning.
Huson, G. (1994). The Architecture and Design of the Network. The Operational Environment. Retrieved from http://www.potaroo.net/papers/1994-6-wkshp/wkshp7.html Network Design Considerations for Cisco Mediator Deployments. (2012). Retrieved from http://www.cisco.com/en/US/docs/solutions/Verticals/Government/mediator-AAG.html